As shown in FIG. 1 of the Prior Case, it is well known to firmly attach dentures to hard dental tissue, such as the jawbone 14 or tooth stubs by an implanted support, via prosthetic dental bridges 10; foundations 12 for such bridges 10 are known. In particular, the dental bridge 10 may be securely mounted to implanted screw posts 16, or other known securing mechanisms. Such foundations 12 are also described, for example, in U.S. Pat. Nos. 5,575,651 and 5,788,492. Other, more readily removable, dentures secured to implanted supports are shown, for example in U.S. Pat. Nos. 5,567,155 and 3,514,858.
The relatively slender implants to support foundations described in the first two patents identified above, and in the Prior Case, were originally considered suitable primarily as short term devices for use until the larger, “permanent” implants healed. One aspect of the present invention continues the earlier development and understanding that the slim implants can be used for substantially permanent, but removable denture prostheses of various types. The devices and procedures of the present invention avoid many of the problems of earlier systems when worn for extended periods, which included the lack of capability for easy removal and replacement, and potential irritation to the patient because of the difficulty of obtaining a proper fit to the jawbone and opposing teeth and gums, or to soft dental tissue.
Thus, a need continued to exist for a system which would permit the placement of a long-lasting dental prosthesis in a patient's mouth by chairside techniques available to the family dentist. Such a system should provide components for mounting such prosthesis, which can be firmly secured to the hard dental tissue, such as the jawbone, in a relatively short time, but which can be adjusted or removed to be prophylactically cleaned or repaired at a later date, and which is readily adaptable to the natural variations in the size and shape of ridges in jaw bones, so as to provide for more comfortable use of any dentures secured on such components.
Certain patients also find it preferable to be able to remove their dentures for daily cleaning. Problems arise with such readily removable systems, however, if a patient's jawbone continues to erode, or otherwise change, under the denture, or the internal portion of the denture is deformed from aging or lengthy use, resulting in a loose fit, lack of function and irritation to the patient's jaw. It is a common practice to bore out and reline existing or new dentures, which were originally made to rest on the gum, and to be retained by a close fit, without the alternative of using a denture adhesive, requiring reapplication each day. In all cases it is important that the denture continue to be accurately retained in the precise position in the jaw, especially relative to the opposing teeth. Any lining or relining must maintain the same or improved fit and retention, by firmly connecting the denture to implanted screws in the identical position regarding the prosthetic teeth.